Recently, in a short field communication authentication technology such as near field communication (NFC), there is a service performed based on intention and behavior of a user while purposely limiting the authentication area. In a case of forming the authentication area with a magnetic field, a loop antenna (coil) is used, and spherical magnetic field distribution is formed on the antenna surface by allowing a current to flow through the antenna. In the radio system using the magnetic field, the distance attenuation property is more precipitous than that in a system using radio waves, and there is an advantage that a boundary of the radio area can be clearly distinguished; however, in order to widely expand the radio area, increase of an amount of the current supplied from a transmitter is required.